<?php
function entity_import_expert(Infinity\Entity &$entity, $field, array $value, array $field_data) {
  $nid = Infinity\Query::select('node', 'n', array(
    'status' => 1, 'title' => $value[0], 'type' => 'expert'
  ))
    ->fields('n', array('nid'))
    ->execute()
    ->fetchField();
  if($nid)
   $entity->fieldManager()->setValue($field, 'target_id', $nid);
}